The present invention relates to a resin composition for encapsulating of a semiconductor comprising a polyether imide compound of high purity, and to a semiconductor apparatus which is coated or encapsulated with the resin composition.
As structural materials for insulation, bonding, and packaging etc. of electronic apparatus and electrical machinery and apparatus,, resins such as the following are used depending on objects to be obtained:
thermosetting resins such as phenolic resin, unsaturated polyester resin, epoxy resin, silicone resin, and polyimide resin etc., and
thermoplastic resins such as nylon, polyacetal, polycarbonate, polyester, polysulfone, polyethersulfone, polyamidoimide, fluorine resin etc.
However, with respect to a resin encapsulating type semiconductor apparatus or a laminated plate of printed circuit, for example, almost all resins which have been used are epoxy resin, silicone resin, and polyimide resin.
Especially, at least 80% of semiconductor products such as transistor, IC, LSI, VLSI, etc. are resin encapsulated types which are transfer fabricated using thermosetting resin, mainly epoxy resin.
A semiconductor chip of semiconductor products is improved every year in integration, and consequently, enlarging of the chip size, thinning of wiring, and multiplication of layers are advanced.
Accordingly, the surface of the semiconductor chip is becoming finer and the thickness of a resin layer of the semiconductor package is gradually becoming thinner.
Also, it has been found that accompanying transfer of the package from pin insertion type to surface package type, the package is exposed to higher temperature (at least 200.degree. C.) at packaging. Therefore, thermal stress caused by difference of thermal expansion coefficients of the resin layer, the semiconductor chip, and a frame etc., which comprise the semiconductor apparatus, is becoming larger, and generation of cracks in encapsulating resin, the semiconductor as well as a passivation film, and short circuiting, cutting and misregistration etc. on the surface of the semiconductor chip easily occur and cause problems.
Under the circumstances described above, polyimide resin has attracted attention as a resin having superior heat resistance and small thermal expansion coefficient, and various kinds of imide resins have been proposed (Japan Pat. No. 1404584, JP-A-1-126321 (1989)). Nevertheless, the imide group resin composition of such prior art do not exhibit sufficient release from a molding die during a molding operation, and the mold release is a crucial problem for practical use of the resin.
One of the objects of the present invention is to provide a resin composition for encapsulating of the semiconductor devices having good molding character, bonding character, electrical characteristics, moisture resistance, and heat resistance etc., and also having superior mold release characteristics to provide a semiconductor apparatus encapsulated with the resin composition.